Magnetorheological fluid (MRF) is a new type of smart fluid material. Under the action of magnetic field, MRF can change from a liquid state to a solid state. When the applied magnetic field is removed, MRF can quickly return to the liquid state. Because of this unique nature of MRF, it is widely used in the field of precision machining.
In the field of micro LED display (Micro LED), in order to manufacture a light emitting diode display, the micro light emitting diodes need to be transferred from an original substrate to the receiving substrate to be aligned in array, which involves precision transferring issues of a huge amount of micro light emitting diodes. In prior art, the micro light emitting diode is generally adsorbed onto a transferring head by electrostatic adsorption and is transferred to the receiving substrate. However, the adsorption capacity of electrostatic adsorption is smaller. The micro light emitting diodes are easily damaged so that the transferring difficulty is high during the transferring process. Moreover, the efficiency of electrostatic adsorption is low.